After waiving defensive end Damontre Moore on Friday, the Giants signed outside linebacker Stansly Maponga on Saturday.
Maponga, 24, spent three seasons with the Falcons, playing 12 games in 2013 and 12 games in 2014. He was waived by the Falcons prior to the regular season.
At 6-foot-2, 265 pounds, Maponga was Atlanta's fifth-round pick out of TCU in 2013. He recorded eight tackles and one sack in his NFL career.
The Giants waived Moore, 23, on Friday after he fought teammate Cullen Jenkins over a pair of free headphones.